There are as many as 300,000 coronary bypass graft procedures performed annually in the United States. Each of those procedures may include one or more graft vessels. Currently, each graft vessel must be hand sutured. As many as four or more grafts are placed in a procedure. Until recently, coronary artery bypass procedures have been performed with the patient on cardiopulmonary bypass whereby the heart is stopped with cardioplegia and the surgery performed on an exposed and still heart.
The previous applications disclosed means and methods for manipulating the heart during cardiac surgery whereby the heart can be located and oriented into the most advantageous position and orientation for beating heart surgery. Reference to those applications is made for a more complete discussion of the means and methods described.
Most particularly, the means and methods described in those applications include using a gross support to support the heart and a means for engaging a selected section of the heart to immobilize that selected section as a surgery target while permitting non-engaged sections of the heart to move in a manner whereby essentially unabated cardiac output is maintained while the heart is regionally immobilized.
The gross support means disclosed in U.S. Pat. No. 6,338,712 includes a flexible cup that can move in a plurality of planes and which has a flexible rim for engaging the heart. The cup is releasably attached to the heart. One means for releasably attaching the cup to the heart includes suction applied by the cup to the heart. Suction is the best mode disclosed in the just-mentioned patent application.
As suction is readily available in most operating rooms, this is an effective means for releasably attaching the elements to the heart. However, this means can be improved.
Therefore, there is a need for a means and method for improving the releasable attachment between the elements of the heart manipulation system disclosed in the referenced patent applications and the heart.
The suction system disclosed in the referenced patent applications can also benefit by being backed up whereby the heart will remain in the desired position and orientation even if vacuum is lost or degraded.
Therefore, there is a need to provide a means for backing up the vacuum system used in the referenced patent applications to releasably attach the elements of the system to the heart.
Operation of the heart was discussed in the referenced patent applications and reference is made thereto for such disclosure so it will not be repeated here.
Recently, there has been interest in minimally invasive coronary bypass surgery. This is not surprising since a median stemotomy and a run on the cardiopulmonary bypass pump are not well tolerated by some patients, combined with the added cost of coronary bypass equipment and staff. The procedure results in considerable recovery time and is associated with a risk of death and major complication. While the ultimate goal is to provide bypass to all vessels by port access (like gallbladder surgery) and to eliminate the need for cardiopulmonary bypass, a more limited but reasonable option for the next number of years will be to perform bypass off pump with an incision (sternotomy or thoracotomy). A tool which could allow performance of multivessel off pump bypass would be most helpful.
Therefore, the referenced patent applications disclosed a heart retractor which will support the heart in position for minimally invasive coronary bypass surgery of coronary arteries, including the circumflex coronary artery, in a manner that will not damage the heart yet will provide easy access to the surgical target without requiring the heart to be stopped yet without unduly constraining the heart. These means and methods can also be improved by having additional means and methods for releasably attaching the elements of the systems to the heart during minimally invasive surgery.